correlation of calcium metabolic axis with urinary stone characteristics

Background: urinary stone disease (usd) refers to the presence of stones or salt crystals within the urinary tract, with calcium stones accounting for approximately 80% of cases. increased urinary calcium and phosphorus excretion predispose individuals to urinary stones, with hypercalciuria being the most significant risk factor. vitamin d plays a pivotal role in modifying urine calcium and phosphorus excretion, and it enhances calcium and phosphorus reabsorption in the kidneys. urinary stone disease is a recognized risk factor for chronic kidney disease (ckd) and may also lead to life-threatening complications such as perinephric abscesses, urosepsis, and urinary tract malignancies. the role of serum vitamin d and its effects on serum calcium and phosphorus in urinary stone formation have been subjects of controversy. objectives: this study aims to evaluate the associations between serum calcium, phosphorus, and vitamin d levels and urinary stones. methods: this retrospective study involved two groups of 90 patients, one with urinary stones and the other without. demographic and biochemical data, including serum calcium, phosphorus, and 25-(oh) vitamin d levels, were recorded for all patients. patients were categorized into four groups based on their serum vitamin d levels: excess, sufficient, insufficient, and deficient. the presence and characteristics of urinary stones were assessed using non-contrast ct scans. results: the mean age of the patients was 54.62 ± 15.46 years. laboratory investigations revealed mean serum calcium, phosphorus, and vitamin d levels of 9.56 ± 0.65 mg/dl, 3.53 ± 0.79 mg/dl, and 25.05 ± 12.96 ng/ml, respectively. this study demonstrated a significant correlation between serum calcium levels and the maximum diameter of urinary stones (correlation = 0.313, p-value = 0.005). no other significant associations were found between serum calcium, serum phosphorus, and serum vitamin d levels and the number of kidney stones, stone laterality, and type of kidney stone. there was also no significant difference between the two groups. conclusions: in conclusion, the role of serum calcium, phosphorus, and 25-(oh) vitamin d levels in urinary stone formation remains controversial. this study suggests that there is no significant association between serum calcium, phosphorus, or 25-(oh) vitamin d and urinary stones, except for a positive association between serum calcium and the diameter of the stone.